Headlamps on motor vehicles require proper aiming, both vertically and horizontally, for safe and optimal performance. From time-to-time, it is necessary to readjust the aim of vehicle headlamps. If the headlamp is not properly adjusted vertically, the headlamp may focus the light too close to the vehicle, not adequately lighting the distance. If the field of light is too short, objects might not be illuminated soon enough for a driver to react to the presence of the object, even if the vehicle is being operated within legal speed limits. Conversely, if the headlamp is aimed to focus too far in the distance, the area in front of the vehicle may not be properly illuminated for adequate recognition of something in front of the vehicle. Further, a headlamp aimed too distant may “blind” an oncoming driver even in the dimmed or “low-beam” condition.
Proper horizontal adjustment is just as important as proper vertical adjustment. If the headlamp is aimed to direct the beam of light too far to the left, oncoming drivers can be blinded. If focused too far left to the right, the primary field directly in front of the automobile may not be properly illuminated. Improperly directed headlamps can be distracting and unsafe.
Many different adjustment assemblies have been used for automobile headlamps; some used more successfully than others. In one known type, a ball stud of an adjustment mechanism is snap fit into a ball socket secured to an associated member in the headlamp assembly. Retainers of this type have ledge members that distort to allow the ball socket to be inserted into a hole of the panel, and spring back against the backside of the panel to prevent the socket from being pulled out. Tab members prevent the socket from being pushed through the panel. Finger members deflect to allow the ball from the stud to be pushed into the socket. The tab members are positioned on quadrants opposite basket members of the socket, and the ledge members are on the same quadrants as the basket members, opposite the fingers.
Insertion force required to push the socket into the panel is high, and often moisturizing is used to facilitate insertion. This requires that the socket be made of hydroscopic material, such as certain types of nylon.
To assemble the system, the ball socket is moisturized and pushed into a hole in the panel. The edge of the panel defining the hole is held between the tab members on one side of the panel and the ledge members on and opposite side of the panel, with the tab members and ledge members on different, but adjacent quadrants. Thereafter, the ball of the stud is pushed into the basket of the socket, deflecting the fingers. The ball socket is designed for five removals and re-insertions of the ball stud for servicing, while still retaining a specified pull-out resistance.
While commonly known ball studs have 10 mm diameter balls, the trend is to use smaller ball studs with, perhaps, 8 mm diameter balls. Many 8 mm ball systems employ a costly undercut on the steel ball stud where the ball portion meets the shaft portion. This feature is used in conjunction with features in the ball socket to increase the pullout force necessary to remove the ball from the socket.
What is needed in the art is an improved ball socket that can be inserted into a panel more easily without moisturizing the socket. What is also needed is an improved ball socket that holds the ball more securely without the need for an undercut on the ball stud.